CFDJ

I started stripping paint yesterday and discovered there really isn't anything under there! So I guess this was a custom frame by someone on their own?

scarlson 

Those stays (seat tube and dropout brazes) really look like Ron Cooper's work. But it would be highly unusual for him to have built a frame with a French threaded bottom bracket.

Any numbers stamped on the steerer?

CFDJ

There are some manufacturer lug angle stamps on the inside of the headset you can vaguely see 73 on top and 60 on bottom of the head tube lugs, 73 on the top tube lug, I also see some other markings I uncovered after stripping the paint that I can't reallt identify.. I agree I saw a lot of ron cooper bikes that were strangely close but I ruled him out for the threading out right too

CFDJ

UPDATE-

The Lugs were made by a company called Bacoma with the marking BCM. I was told they were pretty widely used but it might help narrow down some!

unterhausen

Bocama

I'm curious if the non drive side chainstay socket was fully brazed. The way they built up filler on the rest of the bb shell suggests it wasn't

Andrew R Stewart 

Would you be trying to remember the French Motobacanes that had Swiss threading? These were fairly common in the late 1970s.

This frame was very likely made by a number of people in the factory. It's common to have the various steps of frame construction done at different stations by different workers, for efficiency. I suspect there's a good possibility the person who brazed in the bridges wasn't the one who did the chainstay/drop outs (or the main triangle or the fork...) Andy

CFDJ

I believe it is fully brazed but what might I be looking for to indicate otherwise?

unworthy1

BCM lugs with the FR BB threading sure points hard at this being French, but no idea if the braze-ons are added or OEM, and those DOs with the seat cluster do not ring any bells for me.
If there is any "Gitane" connection then maybe Chas is the guy to call: @verktyg

verktyg 

(biting my tongue)

Is the tubing Metric or Imperial (inch) diameter? That can tell you a WHOLE lot.

Next, what size is the seatpost? Is the headset Metric or Inch?

Most French made bikes used Metric sized tubing even after BBs and headsets changed to British threads. Reynolds, Columbus, Ishiwata, and Tange all produced Metric tubing.

After the switch to ISO (British threads) most French bikes came with 25.4mm (1" inch) steerers and headsets. But... I have a 1986 Bertin with Metric tubing, BB and headset.

machinist42 The correct quote is: "Is it wrong? Or just French"?


To throw a fly into the ointment, in the mid 70's when frame building in the US was just starting to flourish, metric tubing from the Vitus family: Durifort, Vitus 172 and Super Vitus 971 was being sold dirt cheap and Bocama metric lugs and Metric threaded BB shells too.

Back then I built some frames using all of those flavors of tubing. So did a number of top US builders of the day. I had a whole box of Metric sized BB shells with British threads. There were also Imperial sized BB shells with French threads too.

My guess (educated guess) that it's not a production frame made by some big European manufacturer but instead a frame made in the US by a small builder or an individual getting into frame building from the mid 80's. Here's why:

The dropouts, the lugs, braze on derailleur mount and the other braze-ons.

Just because a brand name is on a part or component doesn't mean that company made the product. For example, European forged dropouts were made by several companies who made them for almost everyone in that market including Campagnolo (who had theirs made by at least 2 different suppliers over the years).

The Italian company Technociclo was a major supplier of forged steel dropouts. Whoever made the dropouts on the OP's frame most likely made these Columbus DOs too.




They're different than Vitus DO's.



The lugs are medium point Bocamas without any cutouts. I've never seen this style before. By the mid 80's long point lugs had fallen out of favor with most builders and bike manufacturers because the points had a tendency to lift off of the tube while being brazed leaving a gap between them. So this dates the bike to the mid 80's.

I've never seen a Gitane or Peugeot with a Campy style FD braze-on mount. They used the Simplex style braze-on for a few years which was a much simpler design that never caught on.



Seat stay attachment... Ron Cooper popularized that style of "fast back" stay attachment also known in the UK as "shot in". In 1984 Gitane started using that method on their better quality bikes. Peugeot followed suite a few years latter. The attachment point is different.

1984 Gitane



1988 Peugeot



The design makes for a strong easy to braze connection but one drawback is the distance between the seat stays is narrower at the top which can limit the width of the rear tire to maybe 28mm. That's a 23mm wide tire shown below.



The threaded part brazed into the chain stay bridge looks like 6mm x 1mm "nut" for a mounting recessed rear brake. Why? I've brazed 5mm x .8mm water bottle "top hats" into that location for a number of reasons from a fender mount to a place to attach a sticker flicker thorn catcher.

So what is it??? In French it could be considered a "bâtard" or le salaud... You may never find it's pedigree but it looks like a well made frame so your friend should ride and enjoy it... After all if we trace out ancestry back, we're all barstards! hahaha

verktyg

scarlson 

Eisentraut then?

He's an American framebuilder, active during the time that @verktyg suggests American builders were awash in cheap French materials, and he definitely used this "Ron Cooper-Style" seatstay connection.

And: bâtard is the correct word for something of uncertain parentage. Salaud has nothing to do with illegitimate parentage, it comes from the word sale which means dirty or low-down.

verktyg 

I've been privy to a lot of 'insider info" for many years. Out of respect I don't drop names or quote folks without their prior knowledge and approval. When I say there were "a number of West coast builders", N=???. Think of all the builders who didn't or wouldn't use tubing stickers on their frames.

One reason was they used a blend of tubing to fit what they thought would get the best results regardless of what the un or misinformed customer thought they needed. Another was pure mercantile. Given that most of the top brands of tubing from that era had the same strength and performance, given the same wall thicknesses and so on, the finished frames were about the same!

This 1977 price list shows Reynolds 531 at $30.00 USD a set in bulk while Columbus SP and SL were ~$45.00 USD a set. In 1975 or 76 I bought same Super Vitus 971 Metric tube sets for around $14.00 USD. Later inch size SV 971 was selling for less than $25.00 USD. Tange and Ishiwata weren't easily available a the time but Trek was using Ishiwata and it was so cheap that they sent me a set gratis to evaluate.



Reynolds 531 and 4130 were different alloys with the same properties. Columbus, Tange and Ishiwata were made from 4130. So was Reynolds 501. In the late 70's Columbus started calling their 4130 tubing "Cylex" like it was something special.

Chemical content by weight. Note, Phosphorous and Sulfur are impurities in these alloys and to a degree so is Silicon. These kinds of steels contain less than 5% of elements other than Iron.

Physical properties regarding strength of various steels used in bicycle tubing before the late 70's. Notice the Ultimate and Yield of 4130, Columbus, Reynolds 531 and Super Vitus 971 were all about the same.


Ateliers de la Rive, makers of Super Vitus and other marques played with the metal alloys from the late 1970's until they stopped making steel tubing. Until they introduced Super Vitus 983 in 1983 which was a "supper alloy steel" that contained "micro alloys" the metals they used were high strength low alloy made from high purity steels heat treated to high strength.

There were 2 versions of Super Vitus 980. One had the same main tube 0.9mm x 0.6mm wall thickness as SV 971 and was pretty much the same as Columbus SL. The second version had main tubes with a 0.8mm x 0.5mm wall thickness. It took me a while to track this information down.



In addition to Super Vitus 980 and 983, these un-named builders used Ishiwata and Tange, especially Tange Prestige when it was available cheap!

Eisentraut used that style of seat stay attachment on his Limited models from the mid 1970's but it was a more substantial connection.



OH BTW! Thanks for educating me on the difference between bâtard and salaud meaning dirty or low-down. But many things and people can be BOTH!

verktyg

CFDJ

HI! All this info is completely incredible and I can't thank you enough for compiling this. I will try my best at answering all your questions.

From my measurements I can say that the frame tubes are metric and french according to Sheldon Brown's chart-

TopTube 26mm
Down tube 28mm
seat tube 28mm (with a 26mm seatpost, Maybe not original but it fits well)
Headtube 30.2mm (The headset parts are all threaded french and the sterrer is 22mm)
You're absolutely right that is is a water bottle thread in bridge brazed on the Chainstay tubes.

Thank you again for your info and I completely agree with your sentiment that regardless i feel it's a nice frame and I'm excited to build it up for them. I in the end wanted to hopefully solve this frame mystery I've been sitting on for years before parting ways. and also maybe get some correct decals but I'm not going to lose sleep over that. Learning about this frame had taught me so much about bike frames from that era and that knowledge I have now is invaluable.

verktyg 

If a 26mm seatpost fits well and the seat lug "ears" are not squeezed in like this:



...then the tubing wall thickness is probably 0.8mm which would indicate straight gauge tubing, at least for the seat tube.

Durifort 888, Vitus 888, Vitus 999 and Columbus Aelle all had 0.8mm wall thickness main tubes. Yes, the French used a lot of Columbus Aelle tubing on their mid range bikes.

If the seatpost bolt ears are squished, you can gently spread them with a large screwdriver or chisel coming down from the top. Depending on how much they have been over tightened, you might be able to fit a 26.mm or even larger seatpost. That would suggest a butted seat tube with 0.7mm or 0.6mm wall thickness.

Notice, the slot is straight on this frame. You should also remove any burrs inside the seat tube whether from before or after spreading the slot.



If your don't have a brush hone you can attach some 100 grit sand paper to a wooden dowel and use it to clean and smooth the inside of the seat tube. I hone the inside of the steerer too, It makes adjusting the seatpost and stem height easier.

BTW, light weight straight gauge tubing isn't that bad... Consider the 1.0mm or 0.9mm wall thickness of most common butted tubing vs. 0.8mm thick at the lugs! Makes for a smooth ride and the slight increase in frame weight is negligible for most riders!

I still think that it's a small or custom builder frame.

verktyg

CFDJ

Oh I see what you're saying. The ears aren't bent and there's still plenty of space in between the ears. As I've taken some space from obsessing about this I came across a Swiss brand I wasn't aware of previously. Do you have any info on a brand called Titan? I saw a handful online that has some shocking similarities but couldn't find too much info on their history or catalogues.

verktyg 

Here's your answer. See the translated section:

Titan Bicycles of Switzerland

verktyg